Manufacture of steel.



Z the open hearth and Bessemer processes, and l open hearth furnace theusual additions of WILLIAM R. WALKER,

MANUFACTURE OF STEEL.

No Drawing, Application filed January 2,

Specification of Letters Patent.

OF NEW YORK, N. Y.

Patented Jan. 3, '1911. 1909. Serial No. 470,342.

To all whom it may concerns Be it known that I, VVILLIAM R. WALKER, ofthe city. county. and State of New York, have invented an Improvement inthe Manufa'cture of Steel, of which the following is a specification.

By my invention I am enabled to improve i greatly the quality of steelmanufactured by l I i 4 thus -with comparatively little addition to thecost to provide a. grade of steel much superior to that which heretoforehas been made. A

In the practice of my invention I take steel which has been finished bythe converter or open hearth processes in the usual way, whether in theacid lined converter or aoidlined open hearth furnace or in a basiclined converter or basic open hearth furnace, and tap it at the end ofthe heat into a ladle or vessel, adding in the ladle or converter orform-manganese or other alloys to bring the steel to the desiredcharacter. In these'respccts my process is like the rocess of steelmanufacture heretofore earned on. When it is in the ladle, however,instead of pouring it immediately into the ingot molds I subject it toelectrical heat applied preferably by introducing electrodes through thecover of the ladle. or by heating the metal by means of an inducedelectric current, and I maintain the steel thus subjected to heat for aconsitlcral'ile time, preferably twenty minutes or thereahout, atthesame temperature or a little higher len'iperature than that .at whit-hitwas tapped from-the furnace. The pur mse of this operation is not tocause any further reduction of the. phosphorus 0r silicon content of thesteel, but to keep it in a quiet condition subjected to heat so as toallow the ferro-n'tanganose or other additions to have their Fullofl'e(:t,'to allow gases to c.-cape from the metal and to permitintermingled slag and other impurities to rise 5 to the surface of themetal. and the steel to i become thorougl'tly quieted. after which it ispoured. No new slag-making materials are introduced into the ladle. It.will be found whenthis practice is followed that the steel can bebrought to the desired condition with much less manganese thanheretofore, thus'eflecting an economy of materials; and by reason of thelessened ercentage of manganese the evil efi'ects w ich are sometimescaused by the formation of car bid of manganese in the steel are largelyprevented. V The steel is also brought to a quiet condition, the evilsof segregation'are largely cured, and lngots are cast much freer fromdefects and cavities than has heretofore been possible.- The temperatureof the steel at the time of pouring is also rendered easilycontrollable, whereby it can be tapped from the furnace and cast at alower temperature and this tends to reduce segregation. The process hasother advantages which will be appreciated by those skilled in the art.

I claim 1. The method of making steel, consisting in treating the metalin an open hearth furnace or Bessemer converter, then withdraw: ing thesteel thus formed into a movable vesso] with the desired alloyadditions, electrically heating the steel in said vessel to maintain itin a molten condition and allow the additions to take effect and permitrise of impurities to the surface and escape of gases,- and then pouringdirect from the electrically heated vessel into mold, substantially asdescribed.

2. The process of making steel, consisting in subjecting the metal totreatment in an open hearth furnace or Bessemer converter, thenwithdrawing the steel thus formed into a movable ladle with the desired.allo addi tions, maintaining it inmolten condltion in saidladle'subject to electrical heat to allow rise of impurities to thesurface. escape of gases and proper action of the additions, and thenpouring direct from said ladle into the mold, substantially asdescribed.

In testimony whereof, I have hereunto set my hand.

WILLIAM R. WALKER Witnesses:

Tl. CLAY REIMER, J12, ANNA E. WALLACE.

